Cross-Reference to Related Application
Reference is made to my commonly assigned, co-pending U.S. patent application Ser. No. 07/580,079 entitled SECURITY SYSTEM WITH SIMPLIFIED INSTALLATION, filed Sep. 4, 1990, now abandoned.
1. Technical Field
This invention relates generally to security, fire, energy control, message, and similar systems (collectively referred to herein as "security systems") which have in common that they are connected to the public switched telephone network for outbound communications; and more particularly to such security systems wherein unauthorized disruption, whether intentional or unintentional, cannot be tolerated.
2. Background Art
Typically, such systems have been installed on the monitored premises as an integral unit consisting of a single housing having a controller, a power supply, communication circuitry connected to the public telephone network, and a user interface such as a keypad or other control panel. While such systems were easily installed, they had to be readily accessible to the user; and thus were easily found by unauthorized persons, such as intruders. Once located, the system was vulnerable to being disabled before an alarm could be transmitted. Also, for convenience and simplification of installation, the unit was sometimes mounted such that accidental destruction or injury to the the unit was possible, especially if heavy equipment was used in the area.
These problems associated with integral unit systems have been solved in the prior art by splitting the functions between an easily accessible user interface and a remote, often hidden, control and communications unit installed in a generally inaccessible area. While such split installations overcome the security problems associated with vulnerable integral units, split installations require special wiring from the control and communications unit to the user interface. This often slows installation and requires specially trained installers. In some municipalities, this also involves the mandatory use of union personnel at significant expense.
Access to house power and a telephone line at the hidden control and communications unit is required. If house power is not available at the selected control and communications unit site near the telephone line entrance point, rewiring is required. Electrical wiring must conform to electrical codes, and most municipalities require inspection after any changes. Licensed electricians are required to perform the changes in most cases, adding yet another cost to the installation of the security system.